How Legion Made That Freaky Chattering-Teeth Sound Effect

The human body is a bag of meat and bones. All it takes is a slight tweak to disgust us at a sensory level: the sight of a broken arm, the smell of singed hair, the feeling of scar tissue. In its second season, Noah Hawley’s Legion seeks to mimic that feeling by unnerving viewers through sound — specifically, the sound of chattering teeth.

It’s revealed in Tuesday night’s season premiere that a disease has afflicted the world, one that causes its victims to freeze in a bolt-upright standing-pose, paralyzed except for their mouths, which open and close in a rapid fashion. Chompers bared, their facial movements emit the sound of enamel on enamel. When the afflicted are quarantined together, the resulting sound is like the clattering of steel locusts in hell. According to Legion sound-supervisor Nick Forshager, the finished product only came after a lot of trial and error, which is common for the show. The script explicitly called for the sound of rapidly clacking teeth, but Hawley left it up to Forshager to determine how he’d concoct it. “It’s really experimental,” the veteran of Breaking Bad, Mozart in the Jungle, and Fargo tells Vulture. “Anything goes. If you have an idea and you wanna try it, you go for it.”

Initially, Forshager’s team tried the most obvious direction: on-set sound from the actors playing the diseased folks. “They actually recorded the microphones on the people as they were chattering their teeth,” he says. “It didn’t have that biting sound that we really needed, so then we had to figure out how we get this to really cut through and be jarring on top of that.”

When that didn’t work, they moved on to the kind of sound creation you might expect from an old-timey radio show. “My sound designer tried things like horse hooves,” Forshager recalls. “He would try to see if he could get them to pitch in a way where we could fill up the room with it. But everything that we tried sounded like fake teeth, like something you’d see with Bugs Bunny or a chattering teeth [toy].”

Next, Forshager turned to people who’d never appeared in front of a camera or a microphone before. “We ended up going around my office and recording people chattering their teeth,” he says with a little laugh. “I’d walk around the office, saying, ‘Chatter your teeth. Let me hear what it sounds like.’ And they’d be looking at me like, What are you talking about? And then I’d make them do it in the studio. Some people, they were fully volunteering to do it. And some people, well, it’s hard on your teeth. It actually kind of hurts after doing it.”

Still, Forshager couldn’t quite nail what he wanted. “It sounds like it would be really simple to just do teeth chattering, but not everybody can do it to where you can actually create a sound,” he says. “We had to find the people that could actually create the sound, and it’s not a very loud sound to begin with … If the mike was too close, it sounded weird, and if you mike it too far back, you didn’t get enough sound.”

Eventually, Forshager found the right kind of microphone (a Neumann condenser mike, for all you audio geeks out there) and recorded what he needed. The final step was distorting the gathered sound. “What I would do is, I would take those [recordings], clean them up, and manipulate them so we can make them go faster or slower. And then we created a bed on top of that original production track to give it this kind of eerie multilevel sound.” Et voilà, the terror of the human skull.

As for Forshager himself, don’t think he merely stood on the sidelines. He included himself in the process, having recorded his own teeth chattering too. “I’ll definitely say my jaw was a little sore,” he recalls. “My teeth were a little sore. I’m sure my dentist didn’t love me slamming my teeth together that hard, but it didn’t break any teeth or anything, thank God.”

But Forshager assures me it was all worth it. I ask if the final audio and video combination grosses him out, and he responds, “When you hear it in context and it’s finished, it does. When you see it finished, it really, every time, makes me pop up. It makes me cringe a little bit.” Mission accomplished.